Tri-Color... Cyanotype

[Lightfire]

Alright guys. I've been working on this process since last summer and I'm finally able to show some interesting results. I was able to get all of the needed colors for CMY printing with chemical toning, without any usage of plants or something like that. So, it's possible to get very clear prints, with a decent color saturation and so on.

Tri-Color cyanotype (color checker)

• Lightfire
• Apr 16, 2025

Looks quite good. But can be improved, of course. One of the first test attempts.

The colors aren't bad, especially because I kinda guessed the exposure time without any real calibration.

Tri-Color Cyanotype (the first attempt)

• Lightfire
• Apr 16, 2025

Looks quite decent, except for a lack of normal yellow. I used a different yellow toning here...

Iron hydroxide isn't the best yellow pigment, but it added a bit of its shade to the picture. Anyway, I like the feeling it gives.

Tri-Color Cyanotype (less successful version)

• Lightfire
• Apr 16, 2025

One of my attempts of the new method of making color cyanotype prints. This one lacks of a...

Quite good, just needed more yellow.

Tri-color cyanotype

• Lightfire
• Apr 16, 2025

One of the test prints using a pretty much new method of getting a full-color cyanotype print

A pretty much calibrated image. Quite close to the original one, maybe a bit calmer and actually having a better white balance. The shadows are a bit weak so far, but finding a way to fix it so far.

For magenta I use nickel salts and for yellow I currently use cadmium salts, so you can guess the pigments I get, There's a little detail that makes it possible, I'm going to give more description to it in another post. Stay tuned!

 

[xiaruan]

The CMY colors are incredibly accurate. I've tried using copper for the red hue and iron hydroxide for yellow, but the color performance was disappointing.

 

[xiaruan]

I hope to have the opportunity to try your method.

 

[F4U]

Actually not too bad for a non digital or non silver based, throwback technology. Although photos 2 and 3 are unrecognizable, except as a spill on the floor.

 

[koraks]

I was able to get all of the needed colors for CMY printing with chemical toning

Wow!
Will you walk us through your process? I'd love to read a writeup!

 

[Lightfire]

The CMY colors are incredibly accurate. I've tried using copper for the red hue and iron hydroxide for yellow, but the color performance was disappointing.

Red/magenta hue has always been a problem for the process. Copper works good in duotone color images.

I hope to have the opportunity to try your method.

I'll definitely write some kind of article about it. When I finish a couple of other images to be able to show more.

Actually not too bad for a non digital or non silver based, throwback technology. Although photos 2 and 3 are unrecognizable, except as a spill on the floor.

Thank you. Those two images have a problem with yellows, so no wonders. Even tho I'd say the third one looks a bit better in reality. But still, kinda too violet obliviously.

Wow!
Will you walk us through your process? I'd love to read a writeup!

I'll definitely prepare an article. Hopefully today. And I'll work on a couple of more images to show all the possibilities of the process.

 

[koraks]

Ah, that's great - thanks so much in advance!

 

[Raghu Kuvempunagar]

I was able to get all of the needed colors for CMY printing with chemical toning, without any usage of plants or something like that.

For magenta I use nickel salts and for yellow I currently use cadmium salts, so you can guess the pigments I get, There's a little detail that makes it possible, I'm going to give more description to it in another post. Stay tuned!

This sounds very interesting and the results you shared are quite amazing! Will look forward to read the details and see more examples.

 

[Lightfire]

An attempt to make a print from RGB analog negatives. It definitely needs to be calibrated, so I'm probably going to stick with screen negatives, as I did before. It doesn't look really bad, but the analog negatives are too thin in the hightlights and in the same time the highlights are quite blocked. In any case, the colors are quite nice. Even the skin color looks pretty much ok. But the overall contrast is quite odd so far. But going to share this attempt with you anyway, because it may be helpfull in the future.

 

[Lightfire]

So, after the unsuccessful attempt I decided to calibrate the continuous tone negatives, fortunately, it didn't really take a long time. And I was able to get a much better contrast for my print. Besides that, you can see that the colors were also improved, that's a great thing for sure
.

 

[Lightfire]

So, the layers look this way:



As you can see, I finally get a decent red instead of orange after the yellow layer, so it's another good sign, I have to say.

The process by itself is based on soaking a blue cyanotype image in nickel and cadmium salts, so the iron could be replaced with those metalls, but unfortunately, it's such a slow process naturally that it would take hours to make it done. And I'm not sure that it's even possible this way, without any additions.

So, ofc you need some kind of chemicals to make it work. It's very simple and you'll be able to make your own tri-color cyanotype prints without any problems, I just want to tune some details, so I'll be able to share the whole process with you. It will happen very soon!

 

[xiaruan]

The process by itself is based on soaking a blue cyanotype image in nickel and cadmium salts, so the iron could be replaced with those metalls, but unfortunately, it's such a slow process naturally that it would take hours to make it done. And I'm not sure that it's even possible this way, without any additions.

You could try my copper-toning method—first reduce Prussian blue to Prussian white, then adjust the color. This accelerates the transition metal substitution of iron.

A new cyanotype toning method?

我想我可能发现了一种新的蓝晒调色方法。我用硫酸铜来调蓝晒法。 我已经在其他帖子中讨论过这个问题，但我相信这种方法值得专门讨论。 https://www.photrio.com/forum/threads/showcase-for-your-hcwps.199853/page-31#post-2885917 您需要什么： 漂白液：6g 柠檬酸钾 + 6g 抗坏血酸溶于 50mL 蒸馏水中。这种溶液可以将普鲁士蓝还原为普鲁士白。 调理液：15g 柠檬酸钾 + 5g 硫酸铜溶于 50mL 蒸馏水中。该溶液将普鲁士白转化为亚铁氰化铜 （I）。 氧化液：向水中加入约 3%...

www.photrio.com

 

[xiaruan]

I've also considered experimenting with other transition metals for this method, but currently lack a proper way to handle heavy metal waste solutions.

 

[Lightfire]

You could try my copper-toning method—first reduce Prussian blue to Prussian white, then adjust the color. This accelerates the transition metal substitution of iron.

A new cyanotype toning method?

我想我可能发现了一种新的蓝晒调色方法。我用硫酸铜来调蓝晒法。 我已经在其他帖子中讨论过这个问题，但我相信这种方法值得专门讨论。 https://www.photrio.com/forum/threads/showcase-for-your-hcwps.199853/page-31#post-2885917 您需要什么： 漂白液：6g 柠檬酸钾 + 6g 抗坏血酸溶于 50mL 蒸馏水中。这种溶液可以将普鲁士蓝还原为普鲁士白。 调理液：15g 柠檬酸钾 + 5g 硫酸铜溶于 50mL 蒸馏水中。该溶液将普鲁士白转化为亚铁氰化铜 （I）。 氧化液：向水中加入约 3%...

www.photrio.com

Thank you very much for your link. I've noticed pretty much the same thing, so probably the results of our experiments can be used together. To make the toning faster or slower, depending on the result you want

 

[Lightfire]

You could try my copper-toning method—first reduce Prussian blue to Prussian white, then adjust the color. This accelerates the transition metal substitution of iron.

A new cyanotype toning method?

我想我可能发现了一种新的蓝晒调色方法。我用硫酸铜来调蓝晒法。 我已经在其他帖子中讨论过这个问题，但我相信这种方法值得专门讨论。 https://www.photrio.com/forum/threads/showcase-for-your-hcwps.199853/page-31#post-2885917 您需要什么： 漂白液：6g 柠檬酸钾 + 6g 抗坏血酸溶于 50mL 蒸馏水中。这种溶液可以将普鲁士蓝还原为普鲁士白。 调理液：15g 柠檬酸钾 + 5g 硫酸铜溶于 50mL 蒸馏水中。该溶液将普鲁士白转化为亚铁氰化铜 （I）。 氧化液：向水中加入约 3%...

www.photrio.com

I've read it finally. I have to say that there are similarities between our processes, even tho I use less chemicals with the same result. But I'm going to test it properly as well. So, thanks again!

 

[xiaruan]

I attempted to soak the sample in nickel acetate, but after overnight immersion, no color change was observed. Did you use a divalent nickel salt (Ni²⁺) in your experiment?

 

[Lightfire]

I attempted to soak the sample in nickel acetate, but after overnight immersion, no color change was observed. Did you use a divalent nickel salt (Ni²⁺) in your experiment?

Yes, I use a divalennt nickel salt, a chloride. Did you just try to soak a cyanotype in it or you used your way of toning?

 

[xiaruan]

Yes, I use a divalennt nickel salt, a chloride. Did you just try to soak a cyanotype in it or you used your way of toning?

Two approaches were tested: one sample was directly soaked in pure nickel acetate solution, while another was first bleached and then soaked in a mixed solution of nickel acetate and potassium citrate. Neither sample exhibited any color change.
I suspect this discrepancy may stem from fundamental differences between nickel chloride and nickel acetate properties. However, procurement difficulties with nickel chloride in my location currently prevent further experimental validation.Perhaps an alternative method utilizing nickel acetate could be developed in subsequent research.

 

[Raghu Kuvempunagar]

Isn't Nickel toning of Cyanotype supposed to shift the tone towards greenish-blue and only slightly?

 

[xiaruan]

Isn't Nickel toning of Cyanotype supposed to shift the tone towards greenish-blue and only slightly?

Some literature I've found indicates that nickel ferrocyanide (Ni₂[Fe(CN)₆]) is a reddish-brown compound.

 

[BHuij]

Amazing! Will be keeping a close eye out here for a step-by-step, hopefully one that even a non-chemist such as myself can follow haha. Would this be workable with trichrome negatives on B&W film (i.e., shot through red, green, blue filters at time of exposure)?

 

[koraks]

The fact that cadmium is involved should be sufficient reason to think twice about the desirability to pursue this as a hobby.

 

[xiaruan]

Similarly, I would never consider using cadmium-containing reagents unless working in a lab equipped to handle heavy metal wastewater.

 

[BHuij]

Even if I decide not to attempt it myself, I'm still very interested in the process.

 

[Raghu Kuvempunagar]

I guess an additional step is needed here to get the magenta image after Nickel toning - a dimethylglyoxime bath? Any way, there is a patent that could be of interest in the context of this work:

GB553377A - Improvements in or relating to the production of three-coloured cinematographic films - Google Patents

553,377. Colour photography. COOTE, J. H. Nov. 14, 1941, No. 14655. Drawings to Specification. [Class 98 (ii)] A multicolour image comprises, in different strata of a single silver halide emulsion layer provided with a gelatin or like supercoating, a magenta image of a nickel compound of a...

patents.google.com